| | Silverthorne, CO | Custer, SD | United States |
| Population | 4,520 | 2,067 | 329,725,481 |
| Female Population | 40.7% | 51.8% | 50.5% |
| Male Population | 59.3% | 48.2% | 49.5% |
| Median Age | 49.9 | 57.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,914 | 2,015 | 309,327,143 |
| Population - 2000 | 3,196 | 1,860 | 285,036,114 |
| Population - 1990 | 1,768 | 1,741 | 251,960,433 |
| Pop. 2000 to Now | 53.5% | 3.6% | 15.6% |
| Pop. 1990 to Now | 177.5% | 10.6% | 30.8% |
| space4 | | | |
| Population Density | 1,123.8 | 817.0 | 93.4 |
| Land Area | 4.0 | 2.5 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Silverthorne, CO | Custer, SD | United States |
| Age 0 to 4 | 2.7% | 4.0% | 5.9% |
| Age 5 to 9 | 5.5% | 4.4% | 6.1% |
| Age 10 to 14 | 3.8% | 3.8% | 6.6% |
| Age 15 to 17 | 2.0% | 2.0% | 3.9% |
| Age 18 to 20 | 1.7% | 3.3% | 4.0% |
| Age 21 to 24 | 0.8% | 3.1% | 5.2% |
| Age 25 to 34 | 11.2% | 6.6% | 13.8% |
| Age 35 to 44 | 12.9% | 7.6% | 12.9% |
| Age 45 to 54 | 15.5% | 13.5% | 12.6% |
| Age 55 to 59 | 9.2% | 6.3% | 6.7% |
| Age 60 to 64 | 12.6% | 9.3% | 6.3% |
| Age 65 to 74 | 18.1% | 18.1% | 9.6% |
| Age 75 to 84 | 4.0% | 12.5% | 4.5% |
| Age 85 and over | 0.0% | 5.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Silverthorne, CO | Custer, SD | United States |
| White | 83.4% | 86.5% | 59.4% |
| Black | 0.0% | 3.1% | 12.2% |
| Asian | 0.0% | 0.4% | 5.6% |
| Native American | 0.0% | 4.1% | 0.6% |
| Hawaiian, Pacific Islander | 1.1% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 1.0% | 1.1% | 3.2% |
| Hispanic | 14.6% | 4.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Silverthorne, CO | Custer, SD | United States |
| Married Population | 45.9% | 54.4% | 49.8% |
| Currently Married | 45.9% | 54.4% | 48.0% |
| Married but Separated | 0.0% | 0.0% | 1.8% |
| Single Population | 54.1% | 45.6% | 50.2% |
| Never Married | 33.6% | 20.8% | 33.8% |
| Divorced | 17.1% | 16.3% | 10.8% |
| Widowed | 3.4% | 8.4% | 5.6% |
| space5 | | | |
| Household Size | 2.52 | 1.97 | 2.60 |
| Households | 1,792 | 977 | 124,010,992 |
| Family Households | 1,159 | 626 | 80,755,759 |
| Married couple, w/children | 11.1% | 13.9% | 30.5% |
| Married couple, no children | 58.9% | 64.1% | 42.9% |
| Non Family Households | 633 | 351 | 43,255,233 |
| Single householder, w/children | 14.2% | 13.9% | 15.8% |
| Single householder, no children | 15.7% | 8.1% | 10.8% |